FIG. 8 shows a circuit block diagram and an operating waveform diagram of a conventional example of a switching power supply device that adopts a non-linear control method (here, a bottom-detecting, constant-on-period method). The switching power supply device shown in FIG. 8 is a step-down DC/DC converter of a synchronous rectification type which generates a desired output voltage OUT by stepping down an input voltage IN.
Examples of conventional technologies in this field are disclosed in Patent Documents 1 to 5 listed below